Frother is added in the froth floatation cell used in ore beneficiation to stabilise the air bubbles (i.e., froth), which will hold the ore particles, but it does not affect the floatability of minerals. Which of the following is not used as a frother?
Cresylic acid
Xanthaies
Pine oil
All 'a' 'b' & 'c'
Correct Answer :
B. Xanthaies
Related Questions
Pick out the wrong statement about nucleate boiling.
Bubble generation is by expansion of entrapped gas/vapour at small cavities in the surface
Surface temperature is greater than the saturation temperature of the liquid
Heat transfer from the surface of the liquid is less than that in film boiling
The temperature is less than that of film boiling
Uniform ramming of sand in green sand moulding process leads to
Reduced chance of gas porosity
Greater dimensional stability of the casting
Uniform flow of molten metal into the mould cavity
Less sand expansion type of casting defect
Brittleness induced due to the presence of sulphur in steel can be reduced by adding
Manganese
Magnesium
Vanadium
Copper
Out of the following the refractive index is the highest for
Glass
Diamond
Brine
Kerosene
Which of the following metals is not subjected to electrolytic refining/purification?
Copper
Zinc
Tin
Aluminium
Which of the following processes follows the hardening process for reducing the hardening strains & increasing the toughness of the steel part?
Anodising
Tempering
Carburising
Annealing
Hot extrusion of aluminium is done in the temperature range of __________ °C.
550-600
450-500
350-400
250-300
Basicity 
of the slag in Indian blast furnace is in the range of
0.7-1.0
1.1-1.4
1.5 - 1.8
2.0 - 2.5
Gage pressure within a spherical droplet of a fluid is 'p'. What will be gage pressure within a bubble of the same size & of the same fluid?
p
2 p
0.5 p
0.25 p
Recrystallisation temperature of steel is __________ °C.
50
300
500
800
Strain hardening effect in a metal subjected to cold working is due to the __________ mechanism.
Fracture
Dislocation
Slip
Twinning
A particle is settling in a liquid under Stokesian conditions. The free falling velocity of the particle is proportional to
√(Particle diameter)
Particle diameter
(Particle diameter)2
(Particle diameter)3
Corrosion of metals cannot be prevented by its
Tempering
Chromising
Aluminising
Alloying
Half life of a radioactive isotope corresponds to the time required for half of the __________ to decay.
Atoms
Neutrons
Nucleons
Electrons
Plants produce carbohydrates from the CO2 present in the atmosphere by
Polymerisation
Photochemical reaction
Oxidation
None of these
With increase in steam pressure, its specific volume decreases
Rapidly first and then slowly
Linearly
Slowly first and then rapidly
Exponentially
Silicon percentage in silicon steel used for electrical equipments is about
1
4.0
8
14
Mild steel has __________ crystal lattice structure.
Face centred cubic (fcc)
Body centred cubic (bcc)
Orthorhombic
Cubic
__________ of hard alloy and tool steel is done to make it easily machinable.
Case carburising
Tempering
Normalising
Annealing
Air intake for an air compressor should be preferably taken from
A site, where cooling towers are located nearby
A site, where open coal yard in located nearby
An air conditioned room maintained at a temperature of 18°C
An outside atmosphere at 10°C
In the acid Bessemer process, the hot metal should have the following composition.
S < 0.05% and P < 0.05%
S < 0.05% and P < 1.5%
S < 0.05% and P > 1.5%
S > 1.5% and P < 0.05%
The malleability of a material is the property by virtue of which it can be rolled or hammered into thin sheets. Which of the following materials has the maximum malleability?
Lead
Copper
Aluminium
Wrought iron
Which of the following is not used as a bearing material?
Copper-lead alloys
Babbitts
Bronzes
Cermets
In case of simple harmonic motion, displacement is proportional to the
Velocity
Acceleration
Both (A) & (B)
Neither (A) nor (B)
For preparation of porous bearings by powder metallurgy, preferred particle shape is
Spherical
Nodular
Irregular
No preferred shape
Which of the following is not a principal alloying element for the structural steel?
Molybdenum
Nickel
Manganese
Chromium
Pick out the wrong statement.
Ductile fracture of a stressed material, which exhibits a large plastic deformation is commonly caused by the formation and coalescence of voids in the necked region
Brittle fracture is caused by the propagation of pre-existing cracks in the material and involves minimum plastic deformation
Fatigue fracture of a material is always brittle in nature and takes place due to the existence of line imperfections
Brittle materials are generally tested in tension
Alloying elements present in Haynes stellite, which has superior performance than high speed steel, are:
Nickel, cobalt & chromium
Tungsten, chromium & cobalt
Manganese, chromium & cobalt
Tungsten, molybdenum & nickel
Electrochemical corrosion can occur, only if __________ is present in contact with metal.
Air
Oxygen
Liquid medium
Gaseous medium
Presence of nickel & chromium in steel does not raise its
Elastic limit
Machining properties
Ductility
Resilience